I have a 2011 astra 1.7 diesel 2011, 66k on the clock.
The problem is when idling the engine sounds as if it's revving but the rev counter sits at a constant place just under 1000,
The engine does not rev violently but it's audible rev idle rev idle,
Of late I seem to have used a little more fuel than usual but just a little, I have had a full diagnostics run on the car and nothing came up, any ideas to what could be causing it?
Thank you in advance